Ex-presidential candidate John Edwards in a letter to a judge is challenging whether his lawyer has a conflict of interest in the criminal case against him for alleged campaign funding violations.
Federal prosecutors have questioned whether Washington lawyer Abbie Lowell can fairly represent Edwards after previously representing two potential witnesses.
From 2008 through early 2011, Lowell worked for Lisa Blue Baron. Her deceased husband provided some of the nearly $1 million used in 2007 to help hide the presidential candidate's then-pregnant mistress.
Edwards said in his letter that he is aware of the issue and waives any potential conflict of interest involving Lowell's past clients.
Wade Smith of Raleigh was forced to withdraw from the case earlier this month after prosecutors raised another potential conflict.
Edwards has pleaded not guilty.